Sunan an-Nasā'ī 2215

The full narration

It was narrated from Abu Hurairah that the Messenger of Allah said:"There is no good deed that the son of Adam does, but between ten and seven hundred Hasanahs will be recorded for him. Allah, the mighty and sublime, said: 'Except fasing, for it is for me and I shall reward for it. He gives up his desires and his food for my sake. Fasting is a shield, and the fasting person has two moments of joy. One when he breaks his fast and another when he meets his Lord. And the smell that comes from the mouth of the fasting person is better before Allah than the fragrance of musk